Updated – Microsoft has officially released the new 64 bit version of windows. This has been available in Beta for well over a year to allow software and hardware manufacturers to be ready for the release.Upon the official release of MS x64, I purchased a new Asus laptop with an athlon64 processor so I could begin my own testing and review of the new OS. Our developers have run this OS for over year. It turns out that the Asus laptops with the AMD 64 bit processors do not support windows x64.
The issue is with a setting (or lack of) in the BIOS for APIC, the Advanced Programmable Interrupt Controller. The Windows x64 install dies immediately. Here is the direct quote from Asus tech support: “Hi, This model is not supporting 64bit based operating system even though the CPU is 64bit-ready.”
The Asus web page did not say these new 64 bit laptops do not support Windows x64. Misleading at best. Who’s bug is this, Microsoft, AMD, or Asus ? In researching my processor of choice to run x64, I overlooked the in depth research of the specific Notebook manufacturer. Winxp32 bit does run well on the Z80k if that is all you ask of it. Asus tech support would not say if or when we could expect a bios upgrade to cure the issue.
In the meantime, it seems that Linux works well on most AMD64 machines and yahoo just posted a similar article: “Head to Head: Linux vs. Windows on 64-Bit Chips“.
Update: “Z80K is not supporting 64 bit windows and no plan to make it supporting in the near future”, Asus replied for the z8000k laptop. Other brands don’t have the problem.
UPDATE May 25th 2005: Asus just emailed us and told us that a BIOS update is currently in testing. Windows 64bit will be eventually supported in these laptops.